Changes In Perimeter Research Articles

Особливості коморбідного перебігу діабетичної ретинопатії при цукровому діабеті 2-го типу та первинної відкритокутової глаукоми

Relevance. Common mechanisms of pathogenesis of diabetic retinopathy (DR) with type 2 diabetes mellitus (DM2) and glaucoma optic neuropathy (GON) with primary open-angle glaucoma (POAG) involve the possibility of their mutual clinical burden. The aim. To explore the features of the combination of DR in DM2 and POAG in terms of progression of the stages of the pathological process. Material and methods. 546 patients were examined (546 eyes): 301 patients (301 eyes) had DM2 and POAG; 164 patients (164 eyes) had DM2 and DR, but did not have POAG; 81 patients (81 eyes) had POAG, but did not have DM2. The DR stage was established according to the American Academy of Ophthalmology classification (2002); POAG stage was determined according to the classification of perimetric changes. Some patients were diagnosed with normal tension glaucoma (NTG; 72 eyes). The DR and GON progression indices in patients with POAG were calculated on the basis of the stage and the duration of the diseases and the patients’ age. The software used for statistical research: MedStat і MedCalc v.15.1 (MedCalc Software bvba). Results. The DR progression (by the ratio of the DR stage to the duration of the DM2) at various combinations with POAG had no significant differences. It increased only when NTG was combined with DM2. GON progression was higher when POAG was combined with DM2. In case of DM2 combined with POAG, the progression of GON was as follows. In the case of its primary development, it was higher in NTG, and when it was connected to DM2 – in POAG. The disease index (the ratio of the primary disease rate to age) was the highest when DM2 was combined with POAG, which made the progression of GON 1.2 times faster (p=0.001). The duration of comorbidity in the POAG + DM2 group was 3-4 years more than in DM2 + POAG and NTG + DM2 groups (p<0.001). No gender differences in the DR and GON progression were found. Conclusions. The studied characteristic of the combination of DR with DM2 and POAG revealed complex and ambiguous mechanism of their possible interaction, which dictates the need for further investigation of the mechanisms of their comorbidity. Keywords: diabetic retinopathy, type 2 diabetes mellitus, primary open-angle glaucoma, comorbidity.

Dental arch perimeter changes as a result from premature loss of primary anterior teeth due to trauma: A case series in infant and pre-school children.

The premature loss of primary anterior teeth in deciduous arches is a controversial topic in the literature, especially due to the lack of robust scientific evidence about the consequences in the arch perimeter space and magnitudes of the effects involved. Evaluate the association between premature loss of primary anterior teeth and dental arch perimeter changes, according to clinical variables as deciduous arch type, erupted primary canines, midline involvement and deleterious oral habits, on infants and pre-school children. Patients with avulsion or referral to extraction due to traumatic dental injuries (TDI) were evaluated. After the tooth loss, two trained operators measured the tooth/teeth space, both with a digital caliper and a dry tip compass. The clinical documentation included photographs and radiographs. Follow-up visits occurred from the baseline and every two months over a 12-month period. Chi-square test was used to evaluate the association between arch perimeter changes and clinical variables (α=0.05). A descriptive statistic was performed to explore the magnitude of space changes, with 95% confidence intervals. Eighteen infants/children (mean, 2.78±1.39years) were included. Nine patients presented space loss (50.0%) (mean, -1.32mm), six patients gained space (33.3%) (mean, +1.55mm), and three patients presented space maintenance (16.7%). Clinical variables did not influence dental arch perimeter changes. Premature loss of primary anterior teeth, as well as deleterious oral habits, deciduous arch type, midline involvement and erupted primary canines, were not associated with dental arch perimeter changes.

Abstract 12701: Combined Allometric Normalization of Ascending Aortic Diameter and Assessment of Complication Risk May Support an Earlier Prophylactic Replacement Preventive of Type a Dissection

Introduction: Guideline recommendations of prophylactic surgery in ascending aortic dilation by maximum aortic diameter (MAD) fail to predict > 50% of type-A dissections (AD). Assessment of post-dissection diameters as reference and lack of somatometric normalization may preclude an appropriate risk estimation. Hypothesis: The combined assessment of Z-score and Svensson-index (cross-area/height) based on pre-dissection aortic diameters may be advantageous to indicate prophylactic ascending aortic replacement. Such an approach would include information on normalized vascular dilatation together with a clinical aortic risk indicator. Methods: During two years (2018-2019), data from 515 AD-patients were prospectively recorded at 32 tertiary Spanish hospitals (Registro Español Síndrome Aórtico-III). Pre-dissection aortic diameters were estimated based on the in vitro observations made by Williams et al. on the perimeter change of normal human aortas after the creation of a dissection (PMID: 9122399). Svensson indexes were correlated with ascending aorta Z-scores using quadratic regression. Results (Figure): Setting thresholds of increased risk at Svensson-index >10 cm 2 /m and aortic dilation at Z-score >3, 59% of patients had low Svensson and low Z-score category, 19% low Svensson but high Z-score and 22% high Svensson and high Z-score. No patient with Svensson-index <10 cm 2 /m and Z-score either < or > 3 had an indication for surgery according to guidelines. Among patients with Svensson-index >10 cm 2 /m and aortic dilation at Z-score >3, approximately 1/3 (32%) would have a surgical indication whereas 2/3 (68%) would not. Conclusions: According to current guidelines, only one third of high Svensson and high Z group (7% of the total cohort) would deserve elective surgery. More proactive guidelines, suggesting replacement of ascending aorta in patients with Svensson-index >10 and Z-score>3, would spare from dissection 22% of current cases.

Change to movement and morphology of the median nerve resulting from steroid injection in patients with mild carpal tunnel syndrome

There are conflicting hypotheses regarding the initial pathogenesis of carpal tunnel syndrome (CTS). One hypothesis characterizes it as inflammation of the median nerve caused by compression, while another hypothesis characterizes CTS as non-inflammatory fibrosis of the subsynovial connective tissue (SSCT). This study aimed to investigate the differences in the ultrasonography parameters before and after a steroid injection, which is effective for CTS, to elucidate the initial pathogenesis of CTS and the mechanisms of action of the injected steroid. Fourteen hands from 14 healthy participants and 24 hands from 24 participants with mild CTS were examined. Dynamic movement and morphology of the median nerve before and after steroid injection were measured. There was no significant difference in the normalized maximal distance of the median nerve, which reflects the degree of fibrosis in the SSCT indirectly, during finger and wrist movements before and after the injection among patients with CTS (p > 0.05). Among the parameters that indirectly reflects the degree of median nerve compression, such as normalized maximal change in the aspect ratio of the minimum-enclosing rectangle (MER), maximal change in the median nerve perimeter, and maximal value of the median nerve cross-sectional area (CSA), statistically significant differences were not observed between values of the normalized maximal change in the aspect ratio of the MER and maximal change in the median nerve perimeter, during finger and wrist movements recorded before and after the injection in patients with CTS (p > 0.05). However, multivariate logistic regression analysis revealed that the change in the normalized maximal value of the median nerve CSA, according to finger and wrist movement was correlated with the administration of the steroid injection (p < 0.05). In conclusion, compared to that noted before steroid injection, the median nerve CSA noted during finger and wrist movements changed significantly after injection in patients with mild CTS. Given the improvement in median nerve swelling after steroid injection, but no improvement in the movement of the median nerve during finger and wrist movements, median nerve swelling due to compression (rather than fibrosis of the SSCT may be the initial pathogenesis of early-stage (mild) CTS, and the fibrous changes around the median nerves (SSCT) may be indicative of secondary pathology after median nerve compression. Further studies are required to validate the findings of our study and confirm the pathogenesis of CTS.

Dental arch changes comparison between expander with differential opening and fan-type expander: a randomized controlled trial.

To compare posterior crossbite correction frequency and dentoalveolar changes of the expander with differential opening (EDO) and the fan-type expander (FE). Two-arm parallel randomized controlled trial. Forty-eight patients from 7 to 11 years of age were allocated into two groups. Twenty-four patients were treated with the EDO and 24 patients were treated with the FE. Block randomization was performed. The study was single blind. Digital dental models were acquired before treatment and 6 months after rapid maxillary expansion. The primary outcomes were crossbite correction rate and maxillary arch width changes. Secondary outcomes were interincisal diastema, arch perimeter, length, size and shape, and mandibular dental arch changes. The final sample comprised 24 patients (13 female and 11 male; mean initial age of 7.62 years) in the EDO group and 24 patients (14 female and 10 male; mean initial age of 7.83 years) in the FE group. The crossbites were corrected in 100 per cent of subjects from EDO group and in 75 per cent of patients in FE group. EDO showed greater increases in maxillary intermolar region (P < 0.001), while the FE demonstrated greater increases in the intercanine distance (P = 0.008). Increase in mandibular inter-first permanent molar distance was slightly greater in the EDO group (mean difference of 0.8 mm). Changes in arch length and perimeter were similar in both groups. Both expanders changed the maxillary arch shape. The post-treatment arch shape was larger in the anterior region for FE and in the posterior region in the EDO group. Discomfort during activation was reported by 54 per cent of the participants. A temporary change in the nasal bridge was reported by one patient from FE group. Maxillary arch width and shape changes were distinct between the EDO and the FE. Greater transversal increases of the anterior and posterior regions were observed for the FE and the EDO, respectively. A slightly greater mandibular spontaneous expansion was observed for the EDO only at the molar region. NCT03705871.

Upregulated PKM2 in Macrophages Exacerbates Experimental Arthritis via STAT1 Signaling.

Recent studies indicate that glucose metabolism is altered in rheumatoid arthritis. We hypothesize that Pkm2, as a key regulatory enzyme of glycolysis pathway, triggers the activation of macrophages (Mφ), which results in proinflammatory cytokine production during the arthritis progress. In this study, Pkm2 was found to be overexpressed in ED1-positive Mφ in spleens and synovial tissues from arthritic rats via immunofluorescence, Western blotting, and quantitative RT-PCR. To reveal the role of Pkm2, Dark Agouti rats were treated with either Pkm2 enzyme inhibitor shikonin or the RNA interference plasmids of Pkm2 and negative control plasmids, respectively, via i.p. injection. Pkm2 intervention could alleviate the severity of pristane-induced arthritis in aspects of the macroscopic arthritis score, perimeter changes of midpaw, and the synovitis and destruction of the bone and cartilage as well as reduce the ED1 and p-Stat1-positive cell population in rat synovial tissues. Silencing Pkm2 by RNA interference in classical activated rat and mouse Mφ resulted in less Tnf-α, Il-1β production via Stat1 signaling. Collectively, Pkm2 is highly expressed in ED1-positive Mφ of spleens and synovial tissues from arthritic rats and promotes Mφ activation via Stat1 signaling. Pkm2 might be a promising selective metabolic target molecule for rheumatoid arthritis treatment.

Correlation between Corneal Elevation Topography and Perimetric Changes in Patients with Primary Open Angle Glaucoma

Aim: The aim of this study is to assess Scheimpflug topographic elevation maps in patients with POAG and correlate the results with their perimetric changes. Methods: This was an analytical observational cross-sectional study. The study included 130 eyes of 70 subjects which were divided into 78 eyes of 44 patients diagnosed with POAG and 52 eyes of 26 control subjects. Measurement of IOP, visual field examination in patients with POAG using Humphrey Field Analyzer (2003 Carl Zeiss Meditec), Germany were done. Subjects were scanned using TMS-5 topographer (Topographic Modeling System, version 5. Tomey Corp. Nagoya, Japan) to measure central corneal thickness, mean anterior keratometry, maximum anterior and posterior topographic elevation maps in the central 3, 5, and 7 mm. Results: 78 patients with POAG classified according to visual field deterioration using Hodapp-Anderson-Parrish grading scale into mild glaucoma 33 eyes, moderate glaucoma 19 eyes, severe glaucoma 26 eyes, and 52 eyes control were included in the study. The mean age of the patients with POAG was 57.82 ± 7.78 years; 22 eyes (50%) were male and 22 eyes (50%) were female. The average age of control subjects was 56.62 ± 8.48 years; 12 eyes (46.2%) were male and 14 eyes (53.8%) were female, average CCT was 530.3 ± 23.58 µm, average mean anterior keratometry (MAK) was 42.97 ± 1.42 D, average maximum anterior elevation (MAE) in 3,5 and 7mm zone was 5.31 ± 2.28, 12.10 ± 6.94 and 44.04 ± 21.99 µm respectively and average maximum posterior elevation (MPE) in 3,5 and 7mm zone was 8.46 ± 2.10, 19.90 ± 9.39 and 62.72 ± 28.82 µm respectively in patients with POAG, whereas average CCT was 543.0 ± 31.02µm, average MAK was 43.11 ± 1.73 D, average MAE in 3,5 and 7mm zone was 4.52 ± 1.97, 5.90 ± 2.71 and 27.19 ± 8.55 µm respectively. Conclusion: Evaluation of corneal elevation topography by scheimpflug imaging showed forward shifting of the anterior and posterior corneal surfaces in POAG.

Infrared meibography allows detection of dimensional changes in meibomian glands following intranasal neurostimulation

PurposePatients with dry eye disease (DED) may suffer from decreased tear break-up time due to meibomian gland (MG) dysfunction. Infrared meibography (IR Meibography) uses infrared wavelength light to visualize meibomian glands in vivo. We aimed to explore the feasibility of using serial IR Meibography imaging to assess morphological changes in MGs as an indirect measure of functionality, following intranasal neurostimulation (ITN). MethodsFifteen DED subjects were prospectively enrolled in a single-center, single-arm study. Changes in MGs were captured using IR meibography (RTVUE-XR, Optovue, Inc. Fremont, CA, USA) on the lower eyelids before and after 3 min of ITN (TrueTear®, Allergan, Dublin, Ireland) use that delivers a microcurrent to sensory neurons of the nasal cavity. The same MGs were selected pre- and post-stimulation, and MG area and perimeter were analyzed by two masked observers. ResultsMean (±SD) pre- and post-stimulation MG areas were 2,187.60 ± 635.88 μm2 and 1,933.20 ± 538.55 μm2, respectively. The mean change in area, 254.49 μm2, representing an 11.6% reduction following ITN use, was statistically significant (p = 0.001). Mean (±SD) pre- and post-stimulation MG perimeters were 235.9 ± 51.38 μm and 222.2 ± 47.72 μm, respectively. The mean change in perimeter, 13.7 μm, representing a 5.81% reduction following ITN use, was statistically significant (p = 0.012). ConclusionsOur study shows that IR meibography can be used to detect immediate changes in gland area and perimeter, an indirect measure of MG activity following intervention by ITN.

Physical and functional complications after surgical treatment for breast cancer

Introduction: The ideal treatment for breast cancer should be carried out by a multidisciplinary team, aiming at the global approach of the patient. It is usually a prolonged process and can cause relevant changes in the lives of patients, such as limited shoulder movement, pain, lymphedema, adherence scarring, sensitive changes, phlebitis, among others. Physical therapy intervention plays an essential role and can prevent and minimize complications, besides enabling functional recovery. It is extremely important that the physical therapy service is aware of the prevalence of the main physical and functional complications and the impact of its intervention. Objective: To assess the main physical and functional complications in the post-surgical treatment of breast cancer. Methods: This is a cross-sectional study in which we analyzed the medical records of patients treated in the Physical Therapy Ambulatory from 2011 to 2016. We obtained data about the surgery, prevalence of pain, changes in perimeter, movement amplitude, evaluation of scapulohumeral rhythm and presence of axillary cording. Results: We assessed the data of 703 patients, whose mean age was 56 years; 50.1% were married, and body mass index pointed to overweight (mean: 26.8kg/m²). Sedentary lifestyle was prevalent (73.7%). The main surgery performed was quadrantectomy, followed by mastectomy. Pain was present, however, in extremely low levels (mean of pain in the Visual Analog Scale on the seventh postoperative day was 2.55); movement amplitude restrictions were higher in the beginning, and functionally reversed during follow-up; scapular dysfunction is also little prevalent (9.9%), with high percentage of long term resolution. The incidence of axillary cording was high (87.9%), which requires special attention. Conclusion: The study allowed to observe the main physical and functional complications after breast cancer treatment, and show the importance and necessity of early physical therapy.

Three-dimensional assessment of transverse dentoskeletal mandibular dimensions after utilizing two designs of fixed mandibular expansion appliance: A prospective clinical investigation.

The aim of this clinical study was to evaluate and compare the dentoskeletal transverse mandibular arch dimensions following the use of two designs of fixed mandibular expanders using cone beam computed tomography (CBCT). Twenty orthodontic patients, 12 females and 8 males, with mean age of 13.4 ± 0.5 years were selected and randomly divided into two equivalent groups; group A consisted of 10 patients (4 boys, 6 girls) who were treated with modified Williams expander and group B consisted of 10 patients (4 boys, 6 girls) who were treated with a two-arm fixed expander. Consistent expansion instructions were given to all patients according to a standardized slow protocol of one quarter turn twice/week for both expanders. Routine orthodontic records as well as mandibular CBCTs were obtained before (T1) and immediately after expansion (T2) to estimate changes in dentoskeletal mandibular transverse dimensions. The data was statistically analyzed and the significance level was set at p ≤ 0.05. Mandibular intercanine, inter-premolar, intermolar widths; and arch perimeter were significantly increased (p ≤ 0.05) following expansion with both fixed expanders. However, the changes in inter-premolar width, intercanine width, and arch perimeter were significantly augmented in two-arm fixed expander group than modified Williams’s group. In contrast, their effects on the skeletal mandibular body width were non-significant (p > 0.05). Both expanders yielded significant and equivalent dentoalveolar effects that were more evident with two-arm fixed expander than the William one. Both fixed designs enhanced mandibular transverse dental dimensions; however, they were unsuccessful to create any considerable skeletal effects.

Advances in Modeling Interactions Between Sea Ice and Ocean Surface Waves

AbstractRecent field programs have highlighted the importance of the composite nature of the sea ice mosaic to the climate system. Accordingly, we previously developed a process‐based prognostic model that captures key characteristics of the sea ice floe size distribution and its evolution subject to melting, freezing, new ice formation, welding, and fracture by ocean surface waves. Here we build upon this earlier work, demonstrating a new coupling between the sea ice model and ocean surface waves and a new physically based parameterization for new ice formation in open water. The experiments presented here are the first to include two‐way interactions between prognostically evolving waves and sea ice on a global domain. The simulated area‐average floe perimeter has a similar magnitude to existing observations in the Arctic and exhibits plausible spatial variability. During the melt season, wave fracture is the dominant FSD process driving changes in floe perimeter per unit sea ice area—the quantity that determines the concentration change due to lateral melt—highlighting the importance of wave‐ice interactions for marginal ice zone thermodynamics. We additionally interpret the results to target spatial scales and processes for which floe size observations can most effectively improve model fidelity.

Evaluation of Spheroid 3D Culture Methods to Study a Pancreatic Neuroendocrine Neoplasm Cell Line.

Pancreatic Neuroendocrine Neoplasms (pNEN) are rare tumors which treatment still represent an important clinical problem, due to the paucity of medical treatments. Due to tumor complexity, techniques as 3D cultures are important to study drug activity in a more realistic model. This study aims to compare three different 3D culture methods in order to understand which one can be considered the best option in terms of experimental easiness and reproducibility in studying the efficacy of a target drug on pNEN. The BON1 cell line was used as a pNEN model and the well-known Receptor Tyrosine Kinase inhibitor Sunitinib was used in order to better investigate the different features of each method. The investigated methods are: (1) 96-well hanging drop plates (HD plates), (2) 24-well plates with a cell-repellent surface, and (3) ultra-low attachment 96-well plates with clear round bottom (ULA plates). The evaluated parameters during the study were: cell seeding, easiness in spheroids formation, morphology, culture maintenance, medium change, spheroids monitoring, picture quality, spheroid perimeter measurement reproducibility error, possibility to perform assays into the seeding plate, overall time of the experiment. Moreover, we investigated how culture methods can influence experimental outcomes evaluating perimeter changes, cell viability and immunohistochemistry of spheroids treated with different Sunitinib concentrations. Results showed that each method has weak and strong points but, considering the easiness of spheroids maintenance and reproducibility results, ULA plates method appears to be the best approach to culture BON1 spheroids and, therefore, to study pNEN.

Classifying Changes in the Consolidation Perimeter in the German Group Accounts Statistics Using Statistical Learning

The Deutsche Bundesbank publishes aggregated rates of change for the revenue, the earnings before interest, taxes, depreciation and amortisation, and the earnings before interest and taxes of the German non-financial groups listed in the Prime Standard of the Frankfurt Stock Exchange. Where there are changes in the consolidation perimeter, it is crucial to ad-just these growth rates to obtain an unbiased impression of economic developments. However, an adjustment is only possible if it is known which groups have undergone a significant change in group structure. To find evidence of changes in perimeter, different statistical learning approaches are tested and combined. This is the first paper to classify changes in the consolidation perimeter for data quality maintenance. A combination of a random forest and a weighted nearest neighbours approach, which are both oversampled, provides the best results. The approach avoids overlooking changes in the consolidation perimeter in an efficient and affordable way.

Transverse and torque dental changes after passive self-ligating fixed therapy: A two-year follow-up study

Self-ligating appliances are purposed to expand the arches, but evidence on stability of the result is lacking. We measured the width of maxillary and mandibular arches and torque changes after treatment with the use of passive self-ligating appliances and assessed stability at the 2-year follow-up. Maxillary and mandibular 3-dimensional (3D) models from 32 subjects (mean initial age 14.9±0.9years), consecutively treated with the use of self-ligating appliances, were obtained before, immediately after, and 2years after treatment. Dental arches were examined with the use of 3D software to evaluate differences in transverse arch dimensions and torque values. An incremental increase of arch widths was recorded, especially regarding maxillary and mandibular premolars. The increase in the transverse diameters was associated with a significant positive torque gain. No significant changes in arch perimeter and depth were recorded. In the retention period, slight significant changes in transverse diameters were recorded, and a transverse diameter constriction detected. Torque values remained almost unchanged in the follow-up period. Transverse arch dimensions, along with torque values, increased significantly after treatment with the use of a passive self-ligating appliance. In the 2years following treatment, a tendency to transverse diameter restriction, especially for the maxillary and mandibular premolars, was observed.

Synthetic Corticotropin Therapy Reduces Microglial Activation in a Rodent TBI Model

Traumatic brain injury (TBI) is a leading cause of mortality/morbidity and is associated with chronic neuroinflammation. Melanocortin receptor (MCR) agonists (e.g., ACTH or adrenocorticotropic hormone) that target MC3R/4R ameliorate inflammation and provide a novel therapeutic approach. Following TBI, quiescent microglia become activated resulting in anti and pro‐inflammatory responses and morphological changes. We examined the effect of Cosyntropin (synthetic ACTH) administration on microglial activation through quantification of microglia morphology in a rodent TBI model. We hypothesized that Cosyntropin administration would reduce injury‐induced microglia morphological changes following experimental TBI in rats. We used CCI in adult Sprague‐Dawley rats, randomized to 4 groups: sham‐vehicle (N = 2), sham‐Cosyntropin (N = 2), CCI‐vehicle (N = 4), and CCI‐Cosyntropin (N = 4). Subcutaneous injections of Cosyntropin (120U/kg/day; West Therapeutic Development; Grayslake, IL) were given 30 minutes after CCI and every 12 hours for 7 days thereafter. Microglia activation was quantified based on morphology. Sectioned brains were immunostained (Iba1) and visualized with diaminobenzidine. Image processing and quantification were conducted with FIJI and FracLac for ImageJ resulting in 15 morphological values/cell. Parameters included cell area, fractal dimension, circularity, and cell perimeter and density. CCI animals exhibited increased microglia in the lesion site with no difference in cell count between vehicle and treated. Microglia from CCI animals exhibited no change in cell area, decreased cell perimeter and increased density and circularity compared to sham animals. Cosyntropin treatment altered CCI‐induced microglia changes in cell area, cell perimeter, and cell density. Cosyntropin‐treated CCI animals showed reduced morphological changes in microglia suggesting a reduced activation state. Decreased activation may decrease long‐term deleterious neuroinflammatory effects and may be mediated by Cosyntropin effects on melanocortin receptor signaling.Support or Funding InformationSupported in part by the Pediatric Epilepsy Research Foundation. Cosyntropin was supplied by West Therapeutic Development (Grayslake, IL).This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Survey of the operational state of the art in conjunction analysis

In the last two decades all major space agencies have established processes for operational conjunction analysis (CA) and collision avoidance (COLA). This work highlights the approaches of ESA, DLR, JAXA, NASA, CNES, and CSA. It is found that commercial satellite operators (Inmarsat, Intelsat, SES, and Eutelsat) do not primarily rely on the same sources of data as the major space agencies; however, a common operational process could be identified. Beside comparing the current operational state of the art, the models and methods used by the Combined Space Operations Center (CSpOC) to compute Conjunction Data Messages were studied. The space situational awareness (SSA) community still heavily depends on data provided by CSpOC; however, alternatives are maturing. Last but not least the operational state of the art is compared to theoretical developments of the SSA community. It is shown that while operational tools and processes meet the current needs, the gap is widening with respect to new high-fidelity methods available in literature (e.g., non-Gaussian uncertainty representations). This gap needs to be reduced for the systems to maintain compatibility to future requirements and expected perimeter changes, as for instance a heavily increased number of conjunction messages due to new sensor systems, such as the space fence radar and mega-constellation operations.

Comparative study between patients with subclinical diabetic retinopathy and healthy individuals in the retinal microvascular changes using optical coherence tomography angiography

Purpose The aim of this study was to compare between patients with subclinical diabetic retinopathy (DR) and healthy individuals in the retinal microvascular changes including vascular density (VD), perfusion density (PD), and foveal avascular zone (FAZ) parameters by using optical coherence tomography angiography (OCTA). Patient and methods A total of 50 individuals were categorized into two groups: group A (healthy individuals) and group B (diabetic patients). Full ophthalmic examination, best-corrected visual acuity, intraocular pressure measurement, fundus fluorescein angiography, optical coherence tomography, and OCTA were done for all patients. Results Statistically significant differences were found between the healthy group and the diabetic group in OCTA parameters. VD and PD were significantly decreased in the diabetic patients (P>0.001). FAZ showed significant changes in area value and perimeter; however, the circularity changes were statistically insignificant. Conclusion OCTA is an effective tool that can provide a noninvasive method in the differentiation between subclinical DR and normal individuals. The FAZ metrics, VD, and PD in patients with subclinical DR showed a significant deviation from the parameters obtained from normal healthy individuals.

Optical Coherence Tomography Angiography Study for Evaluation of Microvascular Changes in the Subclinical Diabetic Retinopathy

Background: diabetic retinopathy is the specific microvascular complication of diabetes mellitus and affects 1 of 3 with DM. DR remains a leading cause of vision loss in working adult population. Patients with severe levels of DR were reported to have poor quality of life and reduced physical, emotional and social well-being, and they utilize more health care resources. Objective: this study aimed to evaluate the vascular density, perfusion density and foveal avascular parameters changes in subjects with diabetes mellitus showing no manifestations of diabetic retinopathy using optical coherence tomography angiography. Methods: 40 subjects were categorized into two groups, group A for healthy subjects and group B for the diabetic subjects. HbA1c, renal functions, liver functions and lipid profile were obtained from each individual. Best corrected visual acuity were obtained from each individual and each were subjected to full ophthalmic examination, IOP measurement, fundus fluorescein angiography FFA, Optical Coherence Tomography OCT and Optical Coherence Tomography Angiography OCTA. Results: statisticallysignificantdifferenceswerefoundbetweenthehealthygroupand the diabeticgroupin OCTA parameters. Full vascular density VD significantly decreases in the diabetic patients even in those showed BCVA ≥ 0.7 and totally intact FFA and OCT (P>0.001). Perfusion density PD also was significantly decreased in the diabetic patients (P>0.001). Foveal avascular zone showed significant changes in area value and perimeter, however the circularity changes were statisticallyinsignificant.Conclusion: using OCTA was proven to be clinically significant in differentiating healthy eyes from diabetic eyes that showed no clinically acceptable hallmarks. So, that the term “Subclinical diabetic retinopathy” was suggestible to refer to a clinical state where the FAZ metrics, vascular density and perfusion density showed a particular deviation from the normal healthy parameters.

Effect of TXNRD2 rs35934224, FOXC1 rs2745599 and rs984253 genetic polymorphisms combinations on the development of primary open-angle glaucoma and their degree of association with the disease

Primary open-angle glaucoma (POAG) is a complex disease caused by numerous genetic and environmental factors, as well as their interaction. In recent studies, the effect of genetic polymorphisms combinations and non-equilibrium linkage of allele genes related to the development of POAG has been proved. The aim of the study was to determine the effect of TXNRD2 rs35934224, FOXC1 rs2745599 and rs984253 genetic polymorphisms combinations on the development of primary open-angle glaucoma and their degree of association with the disease. The study included 93 patients (185 eyes) with POAG stage I-IV and 89 volunteers (178 eyes) control subjects without any types of glaucoma. The patients were divided into four groups according to the degree of perimetric changes (Nesterov A. P., 2008). All patients performed visometry, computer perimetry, tonometry, biomicroscopy, ophthalmoscopy, gonioscopy, keratopahymetry, optical coherent tomography of the optic nerve. Analysis of the TXNRD2 rs35934224, FOXC1 rs2745599 and rs984253 genetic polymorphism with POAG was performed in real time using a polymerase chain reaction (PCR) in Gene Amp® PCR System 7500 (Applied Biosystems, USA) automatic amplifier. In the first stage of the study, the genomic DNA from whole venous blood was isolated using the standard reagents PureLink® Genomic DNA Kit for purification of genomic DNA, manufactured by INVITROGEN (USA). The analysis of polymorphism was carried out using unified test systems of TaqMan Mutation Detection Assays Life-Technology (USA). It was determined that the association with POAG had the genotype C/T*A/A*T/A as by comparing control with all patients, and by stratification – with the 1st, 2nd and 3rd groups of patients. The obtained results showed the evidentiary effect of this genotype combinations on the appearance of POAG, and on its progression by the stages of perimetric changes. The risk of the occurrence of POAG in carriers of genotypes C/T*A/A*T/A was increased by 2.8 times (p&lt;0.001). In this combination, the two polymorphisms had heterozygous genotypes (rs35934224 – C/T, rs984253 – T/A), and the genotype rs2745599 – a mutant homozygote A/A. A combination of genotypes C/C*G/A*T/A was also important for the progression of the disease till stage II, which increased the risk of development of the POAG stage II by 2.9 times (p&lt;0.01) compared to control. The risk of occurrence of the POAG in general and development of stage IV increased the presence of combinations of three minor genotypes T/T*A/A*A/A, which was encountered only in patients with POAG (in stage II – f = 0.025, in the third stage – f = 0.036, and in IV – f = 0.071). In our opinion, it confirmed the proposed working hypothesis of the study and showed that the more genotype combinations have the mutant alleles, the stronger this genotype affects the development of POAG.

Is combined mechanism glaucoma a distinct entity?

Primary adult glaucomas that have an occludable angle with peripheral anterior synechiae which are too few to account for the chronically raised IOP, or the glaucomatous optic neuropathy, do not fit the definition of either POAG or PACG and can be considered as combined mechanism glaucoma (CMG). We aimed to compare the clinical features and anatomical parameters of combined mechanism glaucoma with age, sex, and refraction-matched POAG and chronic PACG eyes. Consecutive adult patients with definitive optic nerve head and perimetric changes of glaucoma were screened at a tertiary care center. All glaucomatous eyes having an IOP > 22mmHg on at least three separate occasions and glaucomatous optic neuropathy consistent with moderate visual field loss in the eye were divided as POAG, PACG, and CMG. Eyes with occludable angles having < 90° of goniosynechiae were diagnosed as CMG. A detailed clinical examination, ocular biometry, and ASOCT were performed in the better eye of all individuals. A total of 93 patients with similar visual field index or pattern standard deviation on perimetry were evaluated: 32 POAG, 31 CMG, and 30 PACG. The mean anterior chamber depth was 3.47 ± 0.37mm in POAG, 2.81 ± 0.32mm in PACG, and 3.06 ± 0.26mm in CMG (p < 0.0001). Mean lens thickness was 4.22 ± 0.27mm in POAG, 4.53 ± 0.35mm in PACG, and 4.44 ± 0.29mm in CMG (p = 0.0004). Iridotrabecular contact on ASOCT was nil in POAG, a mean of 87.60 ± 12.802% in PACG eyes, and 15.23 ± 14.19% in CMG eyes, p < 0.0001. CMG was similar to PACG in terms of corneal diameters and lens thickness and had an axial length in between PACG and POAG. On ASOCT, all parameters had highest values in POAG eyes and the least in PACG eyes, with CMG eyes having values in between the other two groups, p value of < 0.0001 between each group for all parameters. This study has demonstrated significantly different anatomical parameters in eyes with CMG, in addition to the differences on gonioscopy and iridotrabecular contact, indicating that CMG is discernibly dissimilar to PACG and POAG.